Stoichiometry of phosphocreatine and inorganic phosphate changes in rat skeletal muscle.
The apparent T1's of phosphate metabolites were measured during and after series of twitch contractions in gastrocnemius muscles of pentobarbital-anesthetized rats by steady-state progressive saturation using spatially-selective composite pulses. There was no significant change in apparent T1's of inorganic phosphate (Pi), phosphocreatine (PCr), or the three phosphates of ATP. There was a 5-10% decrease in the sum of Pi and PCr integrals, and in the sum of the gamma- and beta- phosphates of ATP during stimulation, but no significant change in the ratio (Pi + PCr)/(gamma-ATP + beta-ATP). The results indicate that there is no selective decrease in NMR observable Pi during or after a series of muscle contractions.
Meyer
R A
RA
Department of Physiology, Michigan State University, East Lansing 48824.
Adams
G R
GR
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D004558:Electric Stimulation; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D009132:Muscles / Q000378:metabolism*; D010710:Phosphates / Q000378:metabolism*; D010725:Phosphocreatine / Q000378:metabolism*; D010758:Phosphorus; D051381:Rats; D011919:Rats, Inbred Strains
D010710:Phosphates; D010725:Phosphocreatine; D010758:Phosphorus; D000255:Adenosine Triphosphate